{ "id": "1502.01560", "version": "v1", "published": "2015-02-05T14:11:28.000Z", "updated": "2015-02-05T14:11:28.000Z", "title": "Mass minimizers and concentration for nonlinear Choquard equations in $\\R^N$", "authors": [ "Hong yu Ye" ], "categories": [ "math.AP" ], "abstract": "In this paper, we study the existence of minimizers to the following functional related to the nonlinear Choquard equation: $$ E(u)=\\frac{1}{2}\\ds\\int_{\\R^N}|\\nabla u|^2+\\frac{1}{2}\\ds\\int_{\\R^N}V(x)|u|^2-\\frac{1}{2p}\\ds\\int_{\\R^N}(I_\\al*|u|^p)|u|^p $$ on $\\widetilde{S}(c)=\\{u\\in H^1(\\R^N)|\\ \\int_{\\R^N}V(x)|u|^2<+\\infty,\\ |u|_2=c,c>0\\},$ where $N\\geq1$ $\\al\\in(0,N)$, $\\frac{N+\\alpha}{N}\\leq p<\\frac{N+\\alpha}{(N-2)_+}$ and $I_\\al:\\R^N\\rightarrow\\R$ is the Riesz potential. We present sharp existence results for $E(u)$ constrained on $\\widetilde{S}(c)$ when $V(x)\\equiv0$ for all $\\frac{N+\\alpha}{N}\\leq p<\\frac{N+\\alpha}{(N-2)_+}$. For the mass critical case $p=\\frac{N+\\alpha+2}{N}$, we show that if $0\\leq V(x)\\in L_{loc}^{\\infty}(\\R^N)$ and $\\lim\\limits_{|x|\\rightarrow+\\infty}V(x)=+\\infty$, then mass minimizers exist only if $0